/**
	the script only works on "input [type=text]"

**/

// don't declare anything out here in the global namespace

(function($) { // create private scope (inside you can use $ instead of jQuery)

    // functions and vars declared here are effectively 'singletons'.  there will be only a single
    // instance of them.  so this is a good place to declare any immutable items or stateless
    // functions.  for example:

	var today = new Date(); // used in defaults
    var months = 'Januari,Februari,Maret,April,Mei,Juni,Juli,Agustus,September,Oktober,November,Desember'.split(',');
	var monthlengths = '31,28,31,30,31,30,31,31,30,31,30,31'.split(',');
  	var dateRegEx = /^\d{1,2}\/\d{1,2}\/\d{2}|\d{4}$/;
	var yearRegEx = /^\d{4,4}$/;

    // next, declare the plugin function
    $.fn.simpleDatepicker = function(options) {

        // functions and vars declared here are created each time your plugn function is invoked

        // you could probably refactor your 'build', 'load_month', etc, functions to be passed
        // the DOM element from below

		var opts = jQuery.extend({}, jQuery.fn.simpleDatepicker.defaults, options);

		// replaces a date string with a date object in opts.startdate and opts.enddate, if one exists
		// populates two new properties with a ready-to-use year: opts.startyear and opts.endyear

		setupYearRange();
		/** extracts and setup a valid year range from the opts object **/
		function setupYearRange () {

			var startyear, endyear;
			if (opts.startdate.constructor == Date) {
				startyear = opts.startdate.getFullYear();
			} else if (opts.startdate) {
				if (yearRegEx.test(opts.startdate)) {
				startyear = opts.startdate;
				} else if (dateRegEx.test(opts.startdate)) {
					opts.startdate = new Date(opts.startdate);
					startyear = opts.startdate.getFullYear();
				} else {
				startyear = today.getFullYear();
				}
			} else {
				startyear = today.getFullYear();
			}
			opts.startyear = startyear;

			if (opts.enddate.constructor == Date) {
				endyear = opts.enddate.getFullYear();
			} else if (opts.enddate) {
				if (yearRegEx.test(opts.enddate)) {
					endyear = opts.enddate;
				} else if (dateRegEx.test(opts.enddate)) {
					opts.enddate = new Date(opts.enddate);
					endyear = opts.enddate.getFullYear();
				} else {
					endyear = today.getFullYear();
				}
			} else {
				endyear = today.getFullYear();
			}
			opts.endyear = endyear;
		}

		/** HTML factory for the actual datepicker table element **/
		// has to read the year range so it can setup the correct years in our HTML <select>
		function newDatepickerHTML () {

			var years = [];

			// process year range into an array
			for (var i = 0; i <= opts.endyear - opts.startyear; i ++) years[i] = opts.startyear + i;

			// build the table structure
			var table = jQuery('<table class="datepicker" cellpadding="0" cellspacing="0"></table>');
			table.append('<thead></thead>');
			table.append('<tfoot></tfoot>');
			table.append('<tbody></tbody>');

				// month select field
				var monthselect = '<select name="month">';
				for (var i in months) monthselect += '<option value="'+i+'">'+months[i]+'</option>';
				monthselect += '</select>';

				// year select field
				var yearselect = '<select name="year">';
				for (var i in years) yearselect += '<option>'+years[i]+'</option>';
				yearselect += '</select>';

			jQuery("thead",table).append('<tr class="top"><th colspan="2"><span class="today" title="Pilih tanggal hari ini">Hari ini</span></th><th colspan="3">&nbsp;</th><th colspan="2"><span class="close">Tutup [X]</span></th></tr>');
			jQuery("thead",table).append('<tr class="controls"><th colspan="7"><span class="prevMonth">&laquo;</span>&nbsp;'+monthselect+yearselect+'&nbsp;<span class="nextMonth">&raquo;</span></th></tr>');
			jQuery("thead",table).append('<tr class="days"><th>M</th><th>S</th><th>S</th><th>R</th><th>K</th><th>J</th><th>S</th></tr>');
			for (var i = 0; i < 6; i++) jQuery("tbody",table).append('<tr><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>');
			return table;
		}

		/** get the real position of the input (well, anything really) **/
		//http://www.quirksmode.org/js/findpos.html
		function findPosition (obj) {
			var curleft = curtop = 0;
			if (obj.offsetParent) {
				do {
					curleft += obj.offsetLeft;
					curtop += obj.offsetTop;
				} while (obj = obj.offsetParent);
				return [curleft,curtop];
			} else {
				return false;
			}
		}

		/** load the initial date and handle all date-navigation **/
		// initial calendar load (e is null)
		// prevMonth & nextMonth buttons
		// onchange for the select fields
		function loadMonth (e, el, datepicker, chosendate) {

			// reference our years for the nextMonth and prevMonth buttons
			var mo = jQuery("select[name=month]", datepicker).get(0).selectedIndex;
			var yr = jQuery("select[name=year]", datepicker).get(0).selectedIndex;
			var yrs = jQuery("select[name=year] option", datepicker).get().length;

			// first try to process buttons that may change the month we're on
			if (e && jQuery(e.target).hasClass('prevMonth')) {
				if (0 == mo && yr) {
					yr -= 1;mo = 11;
					jQuery("select[name=month]", datepicker).get(0).selectedIndex = 11;
					jQuery("select[name=year]", datepicker).get(0).selectedIndex = yr;
				} else {
					mo -= 1;
					jQuery("select[name=month]", datepicker).get(0).selectedIndex = mo;
				}
			} else if (e && jQuery(e.target).hasClass('nextMonth')) {
				if (11 == mo && yr + 1 < yrs) {
					yr += 1;mo = 0;
					jQuery("select[name=month]", datepicker).get(0).selectedIndex = 0;
					jQuery("select[name=year]", datepicker).get(0).selectedIndex = yr;
				} else {
					mo += 1;
					jQuery("select[name=month]", datepicker).get(0).selectedIndex = mo;
				}
			}

			// maybe hide buttons
			if (0 == mo && !yr) jQuery("span.prevMonth", datepicker).hide();
			else jQuery("span.prevMonth", datepicker).show();
			if (yr + 1 == yrs && 11 == mo) jQuery("span.nextMonth", datepicker).hide();
			else jQuery("span.nextMonth", datepicker).show();

			// clear the old cells
			var cells = jQuery("tbody td", datepicker).unbind().empty().removeClass('date');

			// figure out what month and year to load
			var m = jQuery("select[name=month]", datepicker).val();
			var y = jQuery("select[name=year]", datepicker).val();
			var d = new Date(y, m, 1);
			var startindex = d.getDay();
			var numdays = monthlengths[m];

			// http://en.wikipedia.org/wiki/Leap_year
			if (1 == m && ((y%4 == 0 && y%100 != 0) || y%400 == 0)) numdays = 29;

			// test for end dates (instead of just a year range)
			if (opts.startdate.constructor == Date) {
				var startMonth = opts.startdate.getMonth();
				var startDate = opts.startdate.getDate();
			}
			if (opts.enddate.constructor == Date) {
				var endMonth = opts.enddate.getMonth();
				var endDate = opts.enddate.getDate();
			}

			// walk through the index and populate each cell, binding events too
			for (var i = 0; i < numdays; i++) {

				var cell = jQuery(cells.get(i+startindex)).removeClass('chosen');

				// test that the date falls within a range, if we have a range
				if (
					(yr || ((!startDate && !startMonth) || ((i+1 >= startDate && mo == startMonth) || mo > startMonth))) &&
					(yr + 1 < yrs || ((!endDate && !endMonth) || ((i+1 <= endDate && mo == endMonth) || mo < endMonth)))) {

					cell
						.text(i+1)
						.addClass('date')
						.hover(
							function () {jQuery(this).addClass('over');},
							function () {jQuery(this).removeClass('over');})
						.click(function () {
							var chosenDateObj = new Date(jQuery("select[name=year]", datepicker).val(), jQuery("select[name=month]", datepicker).val(), jQuery(this).text());
							closeIt(el, datepicker, chosenDateObj);
						});

					// highlight the previous chosen date
					if (i+1 == chosendate.getDate() && m == chosendate.getMonth() && y == chosendate.getFullYear()) cell.addClass('chosen');
				}
			}
		}

		/** closes the datepicker **/
		// sets the currently matched input element's value to the date, if one is available
		// remove the table element from the DOM
		// indicate that there is no datepicker for the currently matched input element
		function closeIt (el, datepicker, dateObj) {
			if (dateObj && dateObj.constructor == Date)
				el.val(jQuery.fn.simpleDatepicker.formatOutput(dateObj));
			datepicker.fadeOut('fast');//remove();
			datepicker = null;
			jQuery.data(el.get(0), "simpleDatepicker", {hasDatepicker : false});
		}

                function flipDateAndMonth(dateString) {

                    var d = dateString.split('/');
                    return d[1] + '/' + d[0] + '/' + d[2];

                }

        // iterate the matched nodeset
        return this.each(function() {

            // functions and vars declared here are created for each matched element. so if
            // your functions need to manage or access per-node state you can defined them
            // here and use $this to get at the DOM element

			if ( jQuery(this).is('input') && 'text' == jQuery(this).attr('type')) {

				var datepicker;
				jQuery.data(jQuery(this).get(0), "simpleDatepicker", {hasDatepicker : false});

				// open a datepicker on the click event
				jQuery(this).click(function (ev) {

					var $this = jQuery(ev.target);

					if (false == jQuery.data($this.get(0), "simpleDatepicker").hasDatepicker) {

						// store data telling us there is already a datepicker
						jQuery.data($this.get(0), "simpleDatepicker", {hasDatepicker : true});

						// validate the form's initial content for a date
						var initialDate = flipDateAndMonth($this.val());

						if (initialDate && dateRegEx.test(initialDate)) {
							var chosendate = new Date(initialDate);
						} else if (opts.chosendate.constructor == Date) {
							var chosendate = opts.chosendate;
						} else if (opts.chosendate) {
							var chosendate = new Date(opts.chosendate);
						} else {
							var chosendate = today;
						}

						// insert the datepicker in the DOM
						datepicker = newDatepickerHTML();
						jQuery("body").prepend(datepicker);

						// position the datepicker
						var elPos = findPosition($this.get(0));
						var x = (parseInt(opts.x) ? parseInt(opts.x) : 0) + elPos[0];
						var y = (parseInt(opts.y) ? parseInt(opts.y) : 0) + elPos[1];
						jQuery(datepicker).css({position: 'absolute', left: x, top: y});

						// bind events to the table controls
						jQuery("span", datepicker).css("cursor","pointer");
						jQuery("select", datepicker).bind('change', function () {loadMonth (null, $this, datepicker, chosendate);});
						jQuery("span.prevMonth", datepicker).click(function (e) {loadMonth (e, $this, datepicker, chosendate);});
						jQuery("span.nextMonth", datepicker).click(function (e) {loadMonth (e, $this, datepicker, chosendate);});
						jQuery("span.today", datepicker).click(function () {closeIt($this, datepicker, new Date());});
						jQuery("span.close", datepicker).click(function () {closeIt($this, datepicker);});

						// set the initial values for the month and year select fields
						// and load the first month
						jQuery("select[name=month]", datepicker).get(0).selectedIndex = chosendate.getMonth();
						jQuery("select[name=year]", datepicker).get(0).selectedIndex = Math.max(0, chosendate.getFullYear() - opts.startyear);
						loadMonth(null, $this, datepicker, chosendate);
					}

				});
			}

        });

    };

    // finally, I like to expose default plugin options as public so they can be manipulated.  one
    // way to do this is to add a property to the already-public plugin fn

	jQuery.fn.simpleDatepicker.formatOutput = function (dateObj) {
                var day = (dateObj.getDate() < 10) ? '0' + dateObj.getDate() : dateObj.getDate();
                var mnt = ((dateObj.getMonth() + 1) < 10) ? '0' + (dateObj.getMonth() + 1) : (dateObj.getMonth() + 1);

		return day + "/" + mnt + "/" + dateObj.getFullYear();
	};

	jQuery.fn.simpleDatepicker.defaults = {
		// date string matching /^\d{1,2}\/\d{1,2}\/\d{2}|\d{4}$/
		chosendate : today,

		// date string matching /^\d{1,2}\/\d{1,2}\/\d{2}|\d{4}$/
		// or four digit year
		startdate : today.getFullYear() - 5,
		enddate : today.getFullYear() + 1,

		// offset from the top left corner of the input element
		x : 1, // must be in px
		y : 25 // must be in px
	};

})(jQuery);